This standard aims at giving DC interface specifications for various sets of values, where
each comprises the nominal value of power supply voltage, its tolerance, and the worst-case
limit values of the input and output voltages for low voltage integrated circuits.
It also provides two categories of interface specification for each nominal supply voltage –
normal range and wide range. The normal range is based on the nominal industry standard
with typical tolerance of about 10 %. The wide range covers battery operation that extends the
lower limit to a practical value at which the battery will continue to operate.